<?php

if(isset($hello)) echo __LINE__,"\n" ;

$hello = '';

if(isset($hello)) echo __LINE__,"\n" ;

if(empty($hello)) echo __LINE__,"\n" ;

$hello = "Now, I am not empty";

if(empty($hello)) echo __LINE__,"\n" ;

unset($hello);

if(isset($hello)) echo __LINE__,"\n" ;
